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Engine Coolant Temperature Sensor


ENGINE COOLANT TEMPERATURE SENSOR

Description

The engine coolant temperature sensor is installed in the engine coolant passage of the cylinder head. The engine control module judges engine temperature by the sensor output voltage and provides optimum fuel enrichment when the engine is cold.





Circuit Diagram

Troubleshooting Hint

If the fast idle speed is not enough or the engine gives off dark smoke during the engine warm-up operation, the engine coolant temperature sensor might be the causes.





Using Scan Tool








Harness Inspection Procedures

Sensor Inspection

1. Remove engine coolant temperature sensor from the intake manifold.





2. With temperature sensing portion of engine coolant temperature sensor immersed in hot water, check resistance.





3. If the resistance deviates from the standard value greatly, replace the sensor.